2G P0170 and P0125, fuel pressure regulator?

[dale187]

Ok guys after researching the engine codes p170 and p125 the anything left is fuel pressure. I have a feeling this is going to be the fix because my car is running super super rich. So for now since i have nothing done to my ecu or any tuning software yet im going to bypass the adjustable fpr i have now and put a stock one on it. My question for you guys is if i do this should i throw in my stock injectors as well or will the stock one manipulate the aftermarket i have in it at the moment? See i want the fuel system to be as stock as possible for now since of course i am running off the wastegate of my 16g so im only pulling 10psi. Also i wanna wait to tinker with that stuff until i get my eprom and dsmlink. Ok last question, anyone know any good online companies i can get a stock fpr for my gsx? Thanks guys

 

[ivatu]

did you check your o2 sensor that causes a lot of problems with the mixture

 

[the_mork]

Are you saying that you have no tuning device at all?

Are you also saying that you aren't using stock injectors?

If so then start by returning to stock injectors or getting something to tune with.

What afpr are your using?

What fuel pump?

Do you have a fuel pressure gauge? If so what is your base fuel pressure? Are you measuring with the vacuum line on or off?

 

[nlzn]

Assuming you aren't running stock injectors because you said you could throw them back in..

I ran my car with a 16g on 10psi exactly with a 255 wally, aeromotive fpr and 550s untuned and it ran like a slug. I knew it would but i had to drive it like that for a day. When I got to tuning with my wideband I was pegging my uego on richness, it won't read below 8. I know exactly how that car feels right now, stock injectors going back in probably wont help much. Id advise getting some AFR readings and leaning out your maps bigtime

 

[dale187]

Yes i tried the o2 sensor.. Waste of 98 dollars . See the thing of it is i think the afpr that i have currently has got to be faulty. I've set the base fp at 43.5 with the line off and it runs incredibly rich to the point that the car wants to shut off. The fuel pressure at the moment reads 21psi thats the only way i could get the car to run decent atall. Sounds fishy right? Even with it reading 21 psi its running extremely rich, no black smoke but im only getting 240 miles to full tank. I dont really know what kind of fuel pump is in it ### i bought the car with everything already done. The injectors i only know they are not stock because i took the serial off the injector and researched it. d1151BA was the code and it came up 550s. I just dont understand what is going on thats why i was going to bypass the apfr and put a stock one on with stock injectors. Until like isaid i canget tuning software and eprom ecu. And possibly a new afpr if it is failing. Do these things fail? I'm so lost.

 

[the_mork]

Change your injectors, they are the reason your running so pig rich. Get some regular 450s and you should be fine, the reason that you need to get down to such a low fuel pressure is that the injector will release less fuel per pulse with less pressure behind it. A dsm ecu cannot compensate for more than about a 12% difference from its optimum fuel maps (450cc injectors and no air leaks). If you are running an aftermarket pump then you can probably get away with as much as 15psi with the original injectors but your safer at about 13psi. Keep in mind for the future that just throwing bigger injectors in without some way to tune them will only hurt performance and you'll hit fuel cut that much faster.

BTW the fact that you can set your fuel pressure to 21 psi means that your afpr does work just fine.

Edit: $98 seriously? When I replaced mine the first place I called had it for $62 and it was the oem replacement not the universal type that you splice in.

 

[dale187]

ok ill do that and ill keep you guys posted. It all makes sense. So after i put the stock injectors back in set the base fp back to 43.5? Then your saying the system should regulate everything the way it needs to get rid of engine code by making the car run smooth and the way it should? thanks for the replies i'm going to throw the injectors in tomorow, unless i decide to wait and just get brand new ones dunno what kind of shape the ones i have are in.

 

[the_mork]

I'd just try them. Yes, return your base fuel pressure to normal. Your other option would be to buy an safc and a logger. I have an safc I'd part with for $130 plus shipping but then you would still need a logger which would be between $50-$120. This would allow you to run your larger injectors and be a bit faster but I would personally start with putting the old injectors in and getting your car running again.

 

[dale187]

Well my goal is first just get the car through inspection. ill ###### ride it like this for a little and then later on i'm going to setup with dsmlink and an eprom. But i want the car to run good right now. You think with the stock fuel system i could bump up the psi a little more than 10?

 

[the_mork]

What fuel pump do you have?


You can pretty safely run 11-12 on a totally stock system, you can probably run 13-15 with just an upgraded fuel pump if you have a logger and watch to see if the car is pulling timing.

I don't really like RRE but they have some great information about halfway down this page is a chart on what you need to run some approximate levels of boost. I would not run what they suggest though since that is really at the edge of what I would consider safe and the only way to know for sure is to have a logger, so take what they tell you and run 1-2 psi less.

Road Race Engineering's Eclipse Fuel Delivery Upgrades

 

[dale187]

Stock injectors finally came in last night. Changed them out, set base fp at 43.5 and changed plugs and the car runs beautifully. Drove it for about 30 mins no CEL yet so well see. Thanks for all your help guys. How long you think it takes for check engine light to jump on? Now i'm going to start hooking up my brand new oil pressure and boost/vac gauge =]

 

[the_mork]

When I had fuel trim problems mine came on after about 2 hours of driving but that was with a bad o2 sensor, my bet is that you wont get one anymore.

 

[dale187]

Well that was one of my guesses before theinjectors so ya i already have a brand new one in there =]

 

[Project2G]

P170

You must be logged in to view this image or video.

P125

You must be logged in to view this image or video.

You must be logged in to view this image or video.